1. Field of the Invention
This invention relates to a cordless telephone apparatus having a base unit and a portable unit connected through radio communications more particularly it relates an improvement of a portable unit for intermittent receiving.
2. Description of the Prior Art
Generally, the portable unit of a cordless telephone apparatus includes a secondary battery which can be charged as a power source. Therefore, to minimize the consumption, it is designed to receive signals intermittently to limit the operating time of the built-in receiver. For example, an intermittent reception of receiving for 100 msec and pausing for 900 msec is repeated. When there is a call from the base unit, it is designed to detect during the 100 msec receiving action.
In such intermittent receiving action, however, if there is a call from the base unit right after the 100 msec receiving action, a maximum no-response time of 900 msec occurs. This aroused dissatisfaction among the users. This problem may be solved by operating the receiver of the portable unit in continuous receiving action. However, this will accelerate the consumption of the secondary battery, and the battery must be exchanged frequently.